Optimized security association database management on home/foreign agent

1. A computer implemented method in a foreign agent comprising:

in response to a first mobile network registration request from a mobile node, accessing a remote authentication facility to retrieve a security association for the mobile node for authenticating and providing a first network connectivity to the mobile node, wherein the security association is associated with a lifespan that specifies the time period in which the security association will be valid;

inserting the security association in a local security association database in the foreign agent to create a security association entry that is active, wherein the security association entry includes the lifespan;

transmitting the first mobile network registration request to a home agent;

responsive to receiving from the home agent a first authentication reply that indicates that the mobile node is authenticated, providing the mobile node with the first network connectivity by binding a first Care-of-Address for the mobile node to a home address associated with the mobile node;

terminating the first network connectivity including removing the binding of the first Care-of-Address and the home address;

responsive to the step of terminating the first network connectivity, modifying the security association entry to indicate that the security association is idle;

receiving a second mobile network registration request from the mobile node after the first network connectivity has been terminated;

responsive to determining that the lifespan associated with the security association is valid, using the security association entry in the local security association database that corresponds to the mobile node to provide authentication of the mobile node without having to access the remote authentication facility;

transmitting the second mobile network registration request to the home agent; and

responsive to receiving from the home agent a second authentication reply that indicates that the mobile node is authenticated, providing the mobile node with a second network connectivity by binding a second Care-of-Address for the mobile node to the home address associated with mobile node, and modifying the security association entry to indicate that the security association is active.

2. The computer implemented method of claim 1 wherein the first and second mobile network registration requests are mobile internet protocol (IP) registration requests.

3. The computer implemented method of claim 1 wherein the lifespan is determined by a local policy or is included with security association, and wherein the security association is retrieved from an authentication, authorization, and accounting (AAA) device.

4. The computer implemented method of claim 1 further comprising,

receiving an updated security association for the mobile node and updating the security association entry in the security association database according to the updated security association; and

upon the security association entry failing to provide authentication of the mobile node, requesting a different security association to provide authentication of the mobile node.

5. The computer implemented method of claim 1 further comprising:

marking the security association as active upon providing the first network connectivity; and

marking the security association entry as expired upon the lifespan expiring.

6. The computer implemented method of claim 5 further comprising,

removing the security association entry upon the security association entry not marked as active and the lifespan expiring; and

removing the security association entry upon reaching a capacity of the security association database and the security association entry is not marked as active and the security association entry is the least recently used.

7. The computer implemented method of claim 6 wherein the capacity of the security association database is defined by a local policy.

8. A network element, comprising:

one or more processors; and

a non-transitory computer-readable medium that stores software, said software comprising:

a security association database to store a set of one or more security associations, wherein each of the set of security associations is associated with a different mobile node, and wherein each of the set of security associations is associated with a lifespan that specifies the time period in which the security association will be valid;

a mobile network registration module to,

receive a network registration request for one of the different mobile nodes,

cause an authentication of that mobile node to be performed by a mobile network authentication module, and

provide network connectivity to that mobile node upon successful authorization including binding a Care-of-Address for that mobile node to a home address associated with that mobile node;

the mobile network authentication module to authenticate the one of the different mobile nodes with the one of the set of security associations stored in the security association database that is associated with that mobile node without having to access a remote authentication facility to retrieve the security association as long as that security association is not expired; and

a security association manager coupled with the security association database, the security association manager to modify the security association entry corresponding to that mobile node in the security association database depending on a current state of the security association, wherein the security association manager is to mark the security association as active upon successful network connectivity, and wherein the security association manager is to mark the security association as idle upon termination of network connectivity and the lifespan not expiring.

9. The network element of claim 8 , wherein the security association manager further removes the security association from the security association database upon the security association entry not marked as active and the lifespan expiring if a capacity of the security association database is met.

10. The network element of claim 8 , wherein if the authentication of the one of the different mobile nodes is not successful, then the mobile network authentication module causing a different security association to be retrieved from the remote authentication facility.

11. The network element of claim 8 , wherein the security association manager further to receive an updated security association for that mobile node and updating the security association entry in the security association database according to the updated security association.

12. The network element of claim 8 , wherein successful network connectivity includes creation of a binding for that mobile node that includes a temporary network address of that mobile node, and wherein deletion of network connectivity includes removing the binding.

13. The network element of claim 8 wherein the security association manager further to insert received security associations into the security association database.

14. The network element of claim 8 , wherein the security association manager further to remove the security association entry upon reaching a capacity of the security association database and the security entry is not marked as active and the security association entry is the least recently used.

15. The network element of claim 14 , wherein the capacity of the security association database is defined by a local policy.

16. A non-transitory machine-readable medium that provides instructions that, if executed by a processor on a foreign agent, will cause said processor to perform operations comprising:

in response to a first mobile network registration request from a mobile node, accessing a remote authentication facility to retrieve a security association for the mobile node for authenticating and providing a first network connectivity to the mobile node, wherein the security association is associated with a lifespan that specifies the time period in which the security association will be valid;

inserting the security association in a local security association database in the foreign agent to create a security association entry that is active, wherein the security association entry includes the lifespan;

transmitting the first mobile network registration request to a home agent;

responsive to receiving from the home agent a first authentication reply that indicates that the mobile node is authenticated, providing the mobile node with the first network connectivity by binding a first Care-of-Address for the mobile node to a home address associated with the mobile node;

terminating the first network connectivity including removing the binding of the first Care-of-Address and the home address;

responsive to the step of terminating the first network connectivity, modifying the security association entry to indicate that the security association is idle;

receiving a second mobile network registration request from the mobile node after the first network connectivity has been terminated;

responsive to determining that the lifespan associated with the security association is valid, using the security association entry in the local security association database that corresponds to the mobile node to provide authentication of the mobile node without having to access the remote authentication facility;

transmitting the second mobile network registration request to the home agent; and

responsive to receiving from the home agent a second authentication reply that indicates that the mobile node is authenticated, providing the mobile node with a second network connectivity by binding a second Care-of-Address for the mobile node to the home address associated with mobile node, and modifying the security association entry to indicate that the security association is active.

17. The non-transitory machine-readable medium of claim 16 wherein the first and second mobile network registration requests are mobile internet protocol (IP) registration requests.

18. The non-transitory machine-readable medium of claim 16 wherein the lifespan is determined by a local policy or is included with security association, and wherein the security association is retrieved from an authentication, authorization, and accounting (AAA) device.

19. The non-transitory machine-readable medium of claim 16 further comprising,

receiving an updated security association for the mobile node and updating the security association entry in the security association database according to the updated security association; and

upon the security association entry failing to provide authentication of the mobile node, requesting a different security association to provide authentication of the mobile node.

20. The non-transitory machine-readable medium of claim 16 further comprising:

marking the security association as active upon providing the first network connectivity; and

marking the security association entry as expired upon the lifespan expiring.

21. The non-transitory machine-readable medium of claim 20 further comprising,

removing the security association entry upon the security association entry not marked as active and the lifespan expiring; and

removing the security association entry upon reaching a capacity of the security association database and the security association entry is not marked as active and the security association entry is the least recently used.

22. The non-transitory machine-readable medium of claim 21 wherein the capacity of the security association database is defined by a local policy.